I would interpret the trend as people tactically switching from the small parties to the main 2, with Brexit Party completely collapsing and Tories picking almost all of them up, while Lib Dems are also on a downtrend that is mirrored by a Labour uptrend, probably the issue of splitting the vote. Very surprising poll regarding class, but might be due to inclusion of pensioners as working class, and the working class leave vote going Tory. And Corbyn doing terribly personally in all polls. All pointing towards a significant Tory majority.